Food Waste Management in UK

Food-Waste-UKFood waste in the United Kingdom is a matter of serious environmental, economic and social concern that has been attracting widespread attention in recent years. According to ‘Feeding the 5K’ organisation, 13,000 slices of crusts are thrown away every day by a single sandwich factory which is featured in the figure above. More recently, Tesco, one of the largest UK food retailers, has published its sustainability report admitting that the company generated 28,500 tonnes of food waste in the first six months of 2013. TESCO’s report also state that 47% of the bakery produced is wasted. In terms of GHG emissions, DEFRA estimated that food waste is associated with 20 Mt of CO2 equivalent/year, which is equivalent to 3% of the total annual GHG emissions.

Globally, 1.2 to 2 billion tonnes (30%-50%) of food produced is thrown away before it reaches a human stomach. Food waste, if conceived as a state, is responsible for 3.3 Bt-CO2 equivalent/year, which would make it the third biggest carbon emitter after China and USA. What makes food waste an even more significant issue is the substantially high demand for food which is estimated to grow 70% by 2050 due to the dramatic increase of population which is expected to reach 9.5 billion by 2075. Therefore, there is an urgent need to address food waste as a globally challenging issue which should be considered and tackled by sustainable initiatives.

A War on Food Waste

The overarching consensus to tackle the food waste issue has led to the implementation of various policies. For instance, the European Landfill Directive (1999/31/EC) set targets to reduce organic waste disposed to landfill in 2020 to 35% of that disposed in 1995 (EC 1999). More recently, the European Parliament discussed a proposal to “apply radical measures” to halve food waste by 2025 and to designate the 2014 year as “the European Year Against Food Waste”. In the light of IMechE’s report (2013), the United Nations Environment Programme (UNEP) in cooperation with FAO has launched the Save Food Initiative in an attempt to reduce food waste generated in the global scale.

In the UK, WRAP declared a war on food waste by expanding its organic waste programme in 2008 which was primarily designed to “establish the most cost-effective and environmentally sustainable ways of diverting household food waste from landfill that leads to the production of a saleable product”. DEFRA has also identified food waste as a “priority waste stream” in order to achieve better waste management performance. In addition to governmental policies, various voluntary schemes have been introduced by local authorities such as Nottingham Declaration which aims to cut local CO2 emissions 60% by 2050.

Sustainable Food Waste Management

Engineering has introduced numerous technologies to deal with food waste. Many studies have been carried out to examine the environmental and socio-economic impacts of food waste management options. This article covers the two most preferable options; anaerobic digestion and composting.

In-vessel composting (IVC) is a well-established technology which is widely used to treat food waste aerobically and convert it into a valuable fertilizer. IVC is considered a sustainable option because it helps by reducing the amount of food waste landfilled. Hence, complying with the EU regulations, and producing a saleable product avoiding the use of natural resources. IVC is considered an environmentally favourable technology compared with other conventional options (i.e. landfill and incineration). It contributes less than 0.06% to the national greenhouse gas inventories. However, considering its high energy-intensive collection activities, the overall environmental performance is “relatively poor”.

Anaerobic Digestion (AD) is a leading technology which has had a rapidly growing market over the last few years. AD is a biologically natural process in which micro-organisms anaerobically break down food waste and producing biogas which can be used for both Combined Heat & Power (CHP) and digestate that can be used as soil fertilizers or conditioners. AD has been considered as the “best option” for food waste treatment. Therefore, governmental and financial support has been given to expand AD in the UK.

AD is not only a food waste treatment technology, but also a renewable source of energy. For instance, It is expected that AD would help the UK to meet the target of supplying 15% of its energy from renewable sources by 2020. Furthermore, AD technology has the potential to boost the UK economy by providing 35,000 new jobs if the technology is adopted nationally to process food waste. This economic growth will significantly improve the quality of life among potential beneficiaries and thus all sustainability elements are considered.

The Role of Biomass Energy in Net-Zero Buildings

The concept of biomass energy is still in its infancy in most parts of the world, but nevertheless, it does have an important role to play in terms of sustainability in general and net-zero buildings in particular. Once processed, biomass is a renewable source of energy that has amazing potential. But there is a lot of work to be done to exploit even a fraction of the possibilities that would play a significant role in providing our homes and commercial buildings with renewable energy.

According to the U.S. Energy Information Administration (EIA), only about 5% of the total primary energy usage in the U.S. comes from biomass fuels. So there really is a way to go.

The Concept of Biomass Energy

Generally regarded as any carbon-based material including plants, food waste, industrial waste, reclaimed woody materials, algae, and even human and animal waste, biomass is processed to produce effective organic fuels.

The main sources of biomass include wood mills and furniture factories, landfill sites, horticultural centers, wastewater treatment plants, and areas where invasive and alien tree and grass species grow.

Whether converted into biogas or liquid biofuels, or burned as is, the biomass releases its chemical energy in the form of heat. Of course, it depends on what kind of material the biomass is. For instance, solid types including wood and suitable garbage can be burned without any need for processing. This makes up more than half the biomass fuels used in the U.S. Other types can be converted into biodiesel and ethanol.

Generally:

  • Biogas forms naturally in landfills when yard waste, food scraps, paper and so on decompose. It is composed mainly of carbon dioxide
  • Biogas can also be produced by processing animal manure and human sewage in digesters.
  • Biodiesel is produced from animal fats and vegetable oils including soybeans and palm oil.
  • Ethanol is made from various crops including sugar cane and corn that are fermented.

How Biomass Fuels Are Used

Ethanol has been used in vehicles for decades and ethanol-gasoline blends are now quite common. In fact, some racing drivers opt for high ethanol blends because they lower costs and improve quality. While the percentage of ethanol is substantially lower, it is now found in most gasoline sold in the U.S. Biodiesel can also be used in vehicles and it is also used as heating oil.

But in terms of their role in net-zero buildings:

  • Wood and wood processing waste is burned to heat buildings and to generate electricity.
  • In addition to being converted to liquid biofuels, various waste materials including some crops like sugar cane and corn can also be burned as fuel.
  • Garbage, in the form of yard, food, and wood waste, can be converted to biogas in landfills and anaerobic digesters. It can also be burned to generate electricity.
  • Human sewage and animal manure can be converted to biogas and burned as heating fuel.

Biomass as a Viable Clean Energy Source for Net-Zero Energy Buildings

Don’t rely on what I say, let’s look at some research, specifically, a study published just last year (2018) that deals with the development of net-zero energy buildings in Florida. It looked at the capacity of biomass, geothermal, hydrokinetic, hydropower, marine, solar, and wind power (in alphabetical order) to deliver renewable energy resources. More specifically, the study evaluated Florida’s potential to utilize various renewable energy resources.

Generating electricity from wind isn’t feasible in Florida because the average wind speeds are slow. The topography and hydrology requirements are inadequate and both hydrokinetic and marine energy resources are limited. But both solar and biomass offer “abundant resources” in Florida. Unlike most other renewable resources, the infrastructure and equipment required are minimal and suitable for use within building areas, and they are both compatible with the needs of net-zero energy.

The concept of net-zero buildings has, of course, been established by the World Green Building Council (GBC), which has set timelines of 2030 and 2050 respectively for new and all buildings to achieve net-zero carbon goals. Simplistically, what this means is that buildings, including our homes, will need to become carbon neutral, using only as much renewable energy as they can produce on site.

But nothing is simplistic when it comes to net-zero energy buildings (ZEB) ). Rather, different categories offer different boundaries in terms of how renewable energy strategies are utilized. These show that net-zero energy buildings are not all the same:

  • ZEB A buildings utilize strategies within the building footprint
  • ZEB B within the site of the property
  • ZEB C within the site but from off-site resources
  • ZEB D generate renewable energy off-site

While solar works for ZEB A and both solar and wind work for ZEB B buildings, biomass and biofuels are suitable for ZEB C and D buildings, particularly in Florida.

Even though this particular study is Florida-specific, it indicates the probability that the role of biomass energy will ultimately be limited, but that it can certainly help buildings reach a net-zero status.

There will be different requirements and benefits in different areas, but certainly professionals offering engineering solutions in Chicago, New York, London (Canada and the UK), and all the other large cities in the world will be in a position to advise whether it is feasible to use biomass rather than other forms of eco-friendly energy for specific buildings.

Biomass might offer a more powerful solution than many people imagine.

Food Waste Management

The waste management hierarchy suggests that reduce, reuse and recycling should always be given preference in a typical waste management system. However, these options cannot be applied uniformly for all kinds of wastes. For examples, food waste is quite difficult to deal with using the conventional 3R strategy.

Of the different types of organic wastes available, food waste holds the highest potential in terms of economic exploitation as it contains high amount of carbon and can be efficiently converted into biogas and organic fertilizer.

There are numerous places which are the sources of large amounts of food waste and hence a proper food waste management strategy needs to be devised for them to make sure that either they are disposed off in a safe manner or utilized efficiently. These places include hotels, restaurants, malls, residential societies, college/school/office canteens, religious mass cooking places, communal kitchens, airline caterers, food and meat processing industries and vegetable markets which generate food residuals of considerable quantum on a daily basis.

anaerobic_digestion_plant

The anaerobic digestion technology is highly apt in dealing with the chronic problem of food waste management in urban societies. Although the technology is commercially viable in the longer run, the high initial capital cost is a major hurdle towards its proliferation.

The onus is on the governments to create awareness and promote such technologies in a sustainable manner. At the same time, entrepreneurs, non-governmental organizations and environmental agencies should also take inspiration from successful food waste-to-energy projects in Western countries and try to set up such facilities in cities and towns.

Behavioral Drivers Behind Food Wastes

food-waste-behaviorBy 2075, the United Nations estimates the global population will peak at 9.5 billion, an extra 3 billion mouths to feed by the end of the century. Meanwhile, while we produce about four billion tonnes of food annually, it is estimated that 30-50% of this never reaches our plates. Of the food that does reach us, some western societies throw away up to a third of all food purchased. This has enormous implications for the global environment, from wasting the water used to grow the food to adverse effects on climate, land and biodiversity.

The drivers behind these phenomenal levels of food waste are complex and include food pricing, logistical and storage issues. However, given the significant level of waste that happens within the households of societies like the UK and US, it is useful and informative to consider those behaviours that drive this level of waste.

The quality of data around food waste, as with much of waste data, has historically been poor. To this end, WRAP commissioned groundbreaking research in the UK in 2006/7 to act as a baseline to their Love Food Hate Waste campaign. This came up with the alarming statistic that 1/3 of food bought by a UK household was thrown away. Until this time, there had been no comprehensive research, either by food manufacturers, retailers or interest groups, suggesting the importance of government, or some other dis-interested party, taking a lead on the issue.

Back to Basics

There may be a link between the amount of time spent preparing food, and the skill and effort that goes into this, and the amount of food waste produced. This has led to a loss of confidence in the kitchen, with individuals losing basic skills that allow them to cook with leftovers, understand food labeling, including Best Before and Use By, even basic storing. WRAP had found little evidence of best practice storage advice so carried out the research themselves – leading the (surprising for many) conclusion that fruit such as apples and pears are best stored in the fridge wrapped in a plastic cover. However, this has masked a larger trend of less time spent in the kitchen, due to demographic changes. This of course begs the question – how should we use this when trying to reduce food waste? Should we encourage people to cook from scratch as a principle?

Although waste prevention and recycling are clearly separated within the waste hierarchy, there are apparent links between the two when considering food waste. There is an urgent need for legislation to enforce separate food waste collections, not only to ensure it was diverted to anaerobic digestion or composting, but also as it led to greater self awareness around food waste. WRAP research has clearly showed a fall in food waste when separate food waste collections were introduced.

Role of Packaging

Historically, packaging has always been a high priority to the public when asked about priorities for reducing waste. However, as awareness of food waste has grown, a more nuanced position has developed among waste managers. While excess packaging is clearly undesirable, and, within the UK for instance, the Courtauld Commitment  has helped reduced grocery packaging by 2.9 million tonnes of waste so far, there is a realization of the importance of food packaging in preserving food and hence reducing food waste.

Making food easily accessible and affordable by many, it could be argued, is one of the crowning achievements of our age. Over the last century, the proportion of household income that is spent on food has plummeted, and there is a direct link to malnutrition and food prices, particularly for children. But does cheap food mean that it is less valued and hence greater wastage? Is the answer expensive food? The evidence from WRAP in the UK is that food waste is still a serious economic issue for households, and underlining the economic case for reducing food waste a major incentive for households, especially as food prices are not entering an era of increase and instability, providing added economic urgency

Political Persuasions

Different political persuasions often differ in the approaches they take to changing behaviours and food waste is no different. In the UK, the Courtauld Commitment is a voluntary agreement aimed at encouraging major retailers to take responsibility mainly for packaging, later growing to encompass food waste, voluntary and so far has seen a 21% reduction in food waste post-consumer.

Meanwhile Wales (in the UK) effectively banned food waste from landfill. Scotland has ensured that businesses make food waste available for separate collection – again it’s only once you see it, you can manage it. Campaigns like the UK’s Love Food Hate Waste have been successful but measuring food waste prevention, as with all waste prevention, is notoriously difficult. But, people are now widely aware of food waste as an issue – we even see celebrity chefs actively talking about food waste reduction and recipes involving leftovers or food that is about to go off.

There is clearly a balance between food waste and food safety, with a commitment to reducing food waste throughout the retail and catering world, not just at home. By engaging environmental health officers to help deliver this, a potentially conflicting message can be delivered in a nuanced and balanced way. Indeed, environmental health officers in Scotland will be responsible for ensuring that Scottish food businesses present their food waste for separate collection.

Role of Communication

It is worth considering how the message should be communicated, and by whom. The community sector are more trusted by the public than government and the private sector are more effective at imparting personal, deeply held beliefs – the sort of beliefs that need to change if we are to see long term changes in attitudes towards consumption and hence waste production.

Furthermore, communications can engage wider audiences that hold an interest in reducing food waste that is perhaps not primarily environmental. The health and economic benefits of issues and behaviours that also result in food waste prevention may be the prevalent message that fits with a particular audience. So whilst the main aim of a training session might be food waste prevention, this is may not be the external message. And this has wider implications for waste prevention, and how we engage audiences around it.

Municipal authorities tasked with waste prevention will need to engage with new groups, in new ways. They will have to consider approaches previously considered to be beyond their powers to engage new audiences – should they be partnering with public health authorities with an interest in nutrition, or social housing providers that are focused on financial inclusion.

Should waste prevention even be a discipline in itself? After all, across material streams it is a motley assortment of behaviours with different drivers. Furthermore, with the knots that one can tie oneself in trying to measure waste that doesn’t get generated, – therefore doesn’t exist – should we integrate waste prevention in to other socio-economic programmes and position it as an “added benefit” to them?

Note: The article is being republished with the permission of our collaborative partner be Waste Wise. The unabridged version can be found at this link. Special thanks to the author Mike Webster.

A Glance at College Recycling Programs

Just one look at your local landfill is enough to convince you that there is a need for more recycling programs. Recycling should be a priority for all institutions across the country. College recycling programs ensure that such institutions make a contribution to environmental conservation.

Every student should have a recycle bin where they dispose of recyclable materials like paper, batteries, water bottles, and so much more. The world is going through a green resource transition, and college institutions should not be left behind.

 

Local communities can also borrow a leaf from college institutions and recycle their waste. The internet is quite resourceful when it comes to researching how a recycling program should work. Students can also use online resources to make their school life easier. For instance, thesis writing services ensure students get the marks they need to graduate.

1. American University

American University strives to be 100% waste-free. Its zero waste policy was adopted in 2010, and since then, the institution has had significant milestones. The system ensures that all university wastes are diverted from landfills. AU uses only renewable materials to ensure no waste is going into the environment.

The university’s environmental conservation efforts ensure it maintains a healthy student community. AU’s fraternity practices sustainable purchasing to maintain an environmentally-friendly campus.

AU makes paper towels from restrooms as well as kitchen wastes. The elimination of water bottles and food trays also helps cut down on wastes. The kitchen grease is recycled for electricity to help manage utility bills.

This institution has one of the finest recycling systems in America’s academic scene. In 2012, the school beat over 600 other universities at a RecycleMania contest.

2. Valencia College

Valencia College has a decade-old recycling system that’s updated each year. The institution has established itself as the model for university sustainability by bagging RecycleMania gold for waste minimization from 2012 through to 2014.

The school encourages students to reduce their waste output. It has a seamless paper, aluminum, plastic, and e-waste management system in place. The school no longer uses water bottles as this is the source of plastic waste in many institutions. Valencia College recycling program aims to reduce the institution’s carbon footprint.

3. College of the Atlantic

College of the Atlantic is well known as the greenest university college in the country. The institution’s recycling system is a comprehensive program that offers outlets for all types of waste.

Aside from outlets for food, the university also has units for composting disposable flatware and kitchen napkins. For foods that cannot be recycled, the campus uses these as a source of renewable energy. The recycling program is run by students to teach them the importance of environmental conservation.

4. University of California

One of University California’s goals is to achieve zero waste by 2020. A 90% waste diversion from landfills will have a significantly positive impact on the environment. The campus also aims to phase out procurement and distribution of Expanded Polystyrene.

Within the institution, is a hub for repurposing items. Students also collect leftover food in their rooms. The school rethinks daily operations to achieve a comprehensive diversion campaign.

5. Kalamazoo College

Kalamazoo College is another higher learning institution with comprehensive waste management and recycling program. The school not only recycles but also donates stationery, mirrors, lamps, and so much more to the surrounding community.

The school’s recycling department handles the exportation of food waste to a local pig farm. Kalamazoo College also recycles e-wastes like batteries, calculators and electric motors.

In addition to recycling, the department also takes up reuse and waste reduction responsibilities. The recycling department is run by students under the supervision of staff in charge. This way, students can understand just how much waste goes into the environment. The campus has two dedicated electric-powered golf carts that help with transportation of waste.

6.     Harvard University

Harvard University is one of the institutions that adopted the single-stream recycling. This means that all recyclable materials are mixed together in one receptacle. This is an effective system because it eliminates any confusion or guesswork.

The school runs a recycling program for different kinds of waste, including e-waste, food, ink, paper, and cartridges. Over the years, the recycling program has evolved and improved in efficacy. The school uses competitions to encourage students to reduce waste.

Conclusion

College recycling programs ensure students learn the importance of environment conservation. Institutions of higher learning are an excellent platform to teach students about environmental friendliness. Diverting waste from landfills ensures they don’t overflow with items that can be reused or recycled.

The Technology Revolutionizing Commercial Waste Management

Every single one of us can do something to improve our impact on the planet, but it is a given that businesses of all sizes have a bigger footprint than families – commercial accounts for 12% of total greenhouse gas emissions. A big factor of that is waste management. From the physical process of picking up garbage, to the methane-released process of decomposition, there are numerous factors that add up to create a large carbon footprint.

Between hiring green focused waste management solutions and recycling in a diligent fashion, there are a few technologies that are helping to break down the barrier between commercial waste management and an environmentally positive working environment.

Cleaning up commercial kitchens

A key form of commercial waste is food waste. Between the home and restaurant, it is estimated by the US Department of Agriculture that 133 billion pounds of food is wasted every year. Much will end up in the landfill. How is technology helping to tackle this huge source of environmental waste? Restaurants themselves are benefiting from lower priced and higher quality commercial kitchen cooking equipment, that helps to raise standards and reduce wastage.

Culinary appliances for varied cuisines also benefit from a new process being developed at the Netherland’s Wageningen University. A major driver of food waste is rejected wholesale delivery, much of which will be disposed of in landfill. The technology being developed in Holland aims to reduce wastage by analyzing food at the source, closer to where recycling will be achievable.

Route optimization

Have you ever received a parcel from an online retailer only to find the box greatly outsizes the contents? On the face of it, this is damaging to the environment. However, many retailers use complex box sorting algorithms. The result is that the best route is chosen on balance, considering the gas needed to make the journey, the amount of stock that can be delivered and the shortest route for the driver. This is an area of intense technological innovation.

The National Waste & Recycling Association reported in 2017 on how 2018 would see further advances, particularly with the integration of artificial intelligence and augmented reality into the route-finding process.

Balancing the landfill carbon footprint

It is well established that landfills are now being used to power wind turbines, geothermal style electricity and so on. They are being improved to minimize the leachate into groundwater systems and to prevent methane escaping into the atmosphere. However, further investigation is being pushed into the possibility of using landfill as a carbon sequester.

AI-based waste management systems can help in route optimization and waste disposal

Penn State University, Lawrence Berkeley and Texas University recently joined together to secure a $2.5m grant into looking into the function of carbon, post-sequestration. This will help to shed light on the carbon footprint and create a solid foundation on which future technology can thrive.

Businesses of all sizes have an impact on the carbon footprint of the world. The various processes that go into making a business profitable and have a positive impact on their local and wider communities need to be addressed. As with many walks of life, technology is helping to bridge the gap.

Food Waste Management and Anaerobic Digestion

Food waste is one of the single largest constituent of municipal solid waste stream. In a typical landfill, food waste is one of the largest incoming waste streams and responsible for the generation of high amounts of methane. Diversion of food waste from landfills can provide significant contribution towards climate change mitigation, apart from generating revenues and creating employment opportunities.

food-waste-biogas

Of the different types of organic wastes available, food waste holds the highest potential in terms of economic exploitation as it contains high amount of carbon and can be efficiently converted into biogas and organic fertilizer. Food waste can either be utilized as a single substrate in a biogas plant, or can be co-digested with organic wastes like cow manure, poultry litter, sewage, crop residues, abattoir wastes etc or can be disposed in dedicated food waste disposers (FWDs). Rising energy prices and increasing environmental concerns makes it more important to harness clean energy from food wastes.

Anaerobic Digestion of Food Wastes

Anaerobic digestion is the most important method for the treatment of food waste because of its techno-economic viability and environmental sustainability. The use of anaerobic digestion technology generates biogas and preserves the nutrients which are recycled back to the agricultural land in the form of slurry or solid fertilizer. The relevance of biogas technology lies in the fact that it makes the best possible utilization of food wastes as a renewable source of clean energy.

A biogas plant is a decentralized energy system, which can lead to self-sufficiency in heat and power needs, and at the same time reduces environmental pollution. Thus, the benefits of anaerobic digestion of food waste includes climate change mitigation, economic benefits and landfill diversion opportunities.

Anaerobic digestion has been successfully used in several European and Asian countries to stabilize food wastes, and to provide beneficial end-products. Sweden, Austria, Denmark, Germany and England have led the way in developing new advanced biogas technologies and setting up new projects for conversion of food waste into energy.

Codigestion at Wastewater Treatment Facilities

Anaerobic digestion of sewage sludge is wastewater treatment facilities is a common practice worldwide. Food waste can be codigested with sewage sludge if there is excess capacity in the anaerobic digesters. An excess capacity at a wastewater treatment facility can occur when urban development is overestimated or when large industries leave the area.

anaerobic_digestion_plant

By incorporating food waste, wastewater treatment facilities can have significant cost savings due to tipping fee for accepting the food waste and increasing energy production. Wastewater treatment plants are usually located in urban areas which make it cost-effective to transport food waste to the facility. This trend is catching up fast and such plants are already in operation in several Western countries.

The main wastewater treatment plant in East Bay Municipal Utility District (EBMUD), Oakland (California) was the first sewage treatment facility in the USA to convert post-consumer food scraps to energy via anaerobic digestion. EBMUD’s wastewater treatment plant has an excess capacity because canneries that previously resided in the Bay Area relocated resulting in the facility receiving less wastewater than estimated when it was constructed. Waste haulers collect post-consumer food waste from local restaurants and markets and take it to EBMUD where the captured methane is used as a renewable source of energy to power the treatment plant. After the digestion process, the leftover material is be composted and used as a natural fertilizer.

The first food waste anaerobic digestion plant in Britain to be built at a sewage treatment plant is the city of Bristol. The plant, located at a Wessex Water sewage works in Avonmouth, process 40,000 tonnes of food waste a year from homes, supermarkets and business across the southwest and generate enough energy to power around 3,000 homes.

Bioenergy Resources in MENA Countries

The Middle East and North Africa (MENA) region offers almost 45 percent of the world’s total energy potential from all renewable sources that can generate more than three times the world’s total power demand. Apart from solar and wind, MENA also has abundant biomass energy resources which have remained unexplored to a great extent.

According to conservative estimates, the potential of biomass energy in the Euro Mediterranean region is about 400TWh per year. Around the region, pollution of the air and water from municipal, industrial and agricultural operations continues to grow.  The technological advancements in the biomass energy industry, coupled with the tremendous regional potential, promises to usher in a new era of energy as well as environmental security for the region.

The major biomass producing countries are Egypt, Yemen, Iraq, Syria and Jordan. Traditionally, biomass energy has been widely used in rural areas for domestic purposes in the MENA region, especially in Egypt, Yemen and Jordan. Since most of the region is arid or semi-arid, the biomass energy potential is mainly contributed by municipal solid wastes, agricultural residues and industrial wastes.

Municipal solid wastes represent the best source of biomass in Middle East countries. Bahrain, Saudi Arabia, UAE, Qatar and Kuwait rank in the top-ten worldwide in terms of per capita solid waste generation. The gross urban waste generation quantity from Middle East countries is estimated at more than 150 million tons annually. Food waste is the third-largest component of generated waste by weight which mostly ends up rotting in landfill and releasing greenhouse gases into the atmosphere. The mushrooming of hotels, restaurants, fast-food joints and cafeterias in the region has resulted in the generation of huge quantities of food wastes.

In Middle East countries, huge quantity of sewage sludge is produced on daily basis which presents a serious problem due to its high treatment costs and risk to environment and human health. On an average, the rate of wastewater generation is 80-200 litres per person each day and sewage output is rising by 25 percent every year. According to estimates from the Drainage and Irrigation Department of Dubai Municipality, sewage generation in the Dubai increased from 50,000 m3 per day in 1981 to 400,000 m3 per day in 2006.

The food processing industry in MENA produces a large number of organic residues and by-products that can be used as biomass energy sources. In recent decades, the fast-growing food and beverage processing industry has remarkably increased in importance in major countries of the region. Since the early 1990s, the increased agricultural output stimulated an increase in fruit and vegetable canning as well as juice, beverage, and oil processing in countries like Egypt, Syria, Lebanon and Saudi Arabia.

The MENA countries have strong animal population. The livestock sector, in particular sheep, goats and camels, plays an important role in the national economy of respective countries. Many millions of live ruminants are imported each year from around the world. In addition, the region has witnessed very rapid growth in the poultry sector. The biogas potential of animal manure can be harnessed both at small- and community-scale.

Renewable Energy from Food Residuals

Food residuals are an untapped renewable energy source that mostly ends up rotting in landfills, thereby releasing greenhouse gases into the atmosphere. Food residuals are difficult to treat or recycle since it contains high levels of sodium salt and moisture, and is mixed with other waste during collection. Major generators of food wastes include hotels, restaurants, supermarkets, residential blocks, cafeterias, airline caterers, food processing industries, etc.

In United States, food scraps is the third largest waste stream after paper and yard waste. Around 12.7 percent of the total municipal solid waste (MSW) generated in the year 2008 was food scraps that amounted to about 32 million tons. According to EPA, about 31 million tons of food waste was thrown away into landfills or incinerators in 2008. As far as United Kingdom is concerned, households throw away 8.3 million tons of food each year. These statistics are an indication of tremendous amount of food waste generated all over the world.

The proportion of food residuals in municipal waste stream is gradually increasing and hence a proper food waste management strategy needs to be devised to ensure its eco-friendly and sustainable disposal. Currently, only about 3 percent of food waste is recycled throughout U.S., mainly through composting. Composting provides an alternative to landfill disposal of food waste, however it requires large areas of land, produces volatile organic compounds and consumes energy. Consequently, there is an urgent need to explore better recycling alternatives.

Anaerobic digestion has been successfully used in several European and Asian countries to stabilize food wastes, and to provide beneficial end-products. Sweden, Austria, Denmark, Germany and England have led the way in developing new advanced biogas technologies and setting up new projects for conversion of food waste into energy.

Anaerobic Digestion of Food Waste

Anaerobic digestion is the most important method for the treatment of organic waste, such as food residuals, because of its techno-economic viability and environmental sustainability. The use of anaerobic digestion technology generates biogas and preserves the nutrients which are recycled back to the agricultural land in the form of slurry or solid fertilizer.

The relevance of biogas technology lies in the fact that it makes the best possible use of various organic wastes as a renewable source of clean energy. A biogas plant is a decentralized energy system, which can lead to self-sufficiency in heat and power needs, and at the same time reduces environmental pollution. Thus, anaerobic digestion of food waste can lead to climate change mitigation, economic benefits and landfill diversion opportunities.

Of the different types of organic wastes available, food waste holds the highest potential in terms of economic exploitation as it contains high amount of carbon and can be efficiently converted into biogas and organic fertilizer. Food waste can either be used as a single substrate in a biogas plant, or can be co-digested with organic wastes like cow manure, poultry litter, sewage, crop residues, slaughterhouse wastes, etc.

A Typical Energy Conversion Plant

The feedstock for the food waste-to-energy plant includes leftover food, vegetable refuse, stale cooked and uncooked food, meat, teabags, napkins, extracted tea powder, milk products, etc. Raw waste is shredded to reduce to its particle size to less than 12 mm. The primary aim of shredding is to produce a uniform feed and reduce plant “down-time” due to pipe blockages by large food particles. It also improves mechanical action and digestibility and enables easy removal of any plastic bags or cling-film from waste.

Fresh waste and re-circulated digestate (or digested food waste) are mixed in a mixing tank. The digestate is added to adjust the solids content of the incoming waste stream from 20 to 25 percent (in the incoming waste) to the desired solids content of the waste stream entering the digestion system (10 to 12 percent total solids). The homogenized waste stream is pumped into the feeding tank, from which the anaerobic digestion system is continuously fed. Feeding tank also acts as a pre-digester and subjected to heat at 55º to 60º C to eliminate pathogens and to facilitate the growth of thermophilic microbes for faster degradation of waste.

From the predigestor tank, the slurry enters the main digester where it undergoes anaerobic degradation by a consortium of Archaebacteria belonging to Methanococcus group. The anaerobic digester is a CSTR reactor having average retention time of 15 to 20 days. The digester is operated in the mesophilic temperature range (33º to 38°C), with heating carried out within the digester. Food waste is highly biodegradable and has much higher volatile solids destruction rate (86 to 90 percent) than biosolids or livestock manure. As per conservative estimates, each ton of food waste produces 150 to 200 m3 of biogas, depending on reactor design, process conditions, waste composition, etc.

Biogas contains significant amount of hydrogen sulfide (H2S) gas that needs to be stripped off due to its corrosive nature. The removal of H2S takes place in a biological desulphurization unit in which a limited quantity of air is added to biogas in the presence of specialized aerobic bacteria that oxidizes H2S into elemental sulfur. The biogas produced as a result of anaerobic digestion of waste is sent to a gas holder for temporary storage. Biogas is eventually used in a combined heat and power (CHP) unit for its conversion into thermal and electrical energy in a co­generation power station of suitable capacity. The exhaust gases from the CHP unit are used for meeting process heat requirements.

The digested substrate leaving the reactor is rich in nutrients like nitrogen, potassium and phosphorus which are beneficial for plants as well as soil. The digested slurry is dewatered in a series of screw presses to remove the moisture from slurry. Solar drying and additives are used to enhance the market value and handling characteristics of the fertilizer.

Diverting Food from Landfills

Food residuals are one of the single largest constituents of municipal solid waste stream. Diversion of food waste from landfills can provide significant contribution towards climate change mitigation, apart from generating revenues and creating employment opportunities. Rising energy prices and increasing environmental pollution makes it more important to harness renewable energy from food scraps.

Anaerobic digestion technology is widely available worldwide and successful projects are already in place in several European as well as Asian countries that makes it imperative on waste generators and environmental agencies to root for a sustainable food waste management system.

Best Ways for Your College to Go Green

college-greenToday a lot of colleges have made an environmental revolution. No more coffee to go, no more plastic bottles to buy on a territory of the campus, the implementation of eco-friendly projects and campaigns – all this now is becoming a sustainable lifestyle for the majority of students.

The effects of climate change are dramatically terrifying. In most colleges, the initiative of the activities to make planet safer comes from administration faculties. However, any little action of every student will help to protect our Earth. Let’s see now how green we may be in a range of college life.

Today you even may look for the university that has its degrees in eco subjects: such as sustainable agriculture, natural resources conservation and indoor gardening and so on.

Energy supply

Whether it is a constructing of building with more efficient environmentally substantial windows and panels that use solar, wind or even water power, during past several years the colleges become a way eco-friendlier. Some programs promote the conservation in any aspect and the composting bins.

Using electronics instead of paper

The world now is digitally focused, and this is good news for a planet. A lot of colleges are equipped with computer classes, electronic libraries, and online testing programs. You may also have with taking notes electronically in order not to waste paper and money on buying notebooks. Instead of buying a book, prefer to borrow it or get only if necessary.

To see and read more more living a sustainable and healthy life, check out the Public Goods Blog by clicking here.

Opening a refectory with a local eco food

Organic food and organic gardening is a modern, healthy part of a sustainable lifestyle. The most colleges now have the individual spaces for organic gardening where any student can work to show their faith-based actions. They can grow plants, vegetables or fruits that are used in the kitchen of the campus for preparing healthy food.

The administration of some universities now got rid of trays – they state it will prevent students from over-eating and wasting food. Instead, a student takes a plate where he can put only as much as he can eat.

Having a place for refilling a water bottle

As you know, only 20% of plastic bottles will be recycled. Tthe question is that where did other 80% proceed to? The management of some colleges take concrete measures to fight this issue: they don’t sell plastic bottles on the territory of campus. As an alternative, they give reusable water bottles and provide with stations of water filling. Isn’t it an amazingly simple and useful to evolve an initiative to become environmentally conscious?

Special campaigns for students

It is important for colleges to have some green project ideas for college students that may evolve students to concrete actions toward the protection of an ecology. It can be something like tree planting, street cleaning or any other environment-themed campaigns.

Organic food is a modern, healthy part of a sustainable lifestyle.

Organic food is a modern, healthy part of a sustainable lifestyle.

The effective way to make the more environmentally sustainable community is creating a communication between students and management. Every student may have his fresh ideas of go green, and it ‘d be good and if the management could encourage them and help to realize.

Transportation

What doesn’t student dream of having his car? But don’t lie to yourself – it is not a secret that the cars are the biggest reason of pollution in the air. Just think about it – do you need a car? Taking a public transport or having a bicycle will not only save a planet but also will save your money.

Many colleges offer carpool boards which allow pairing riders with drivers and a shuttle bus which run on biodiesel that is much safer for the planet than any other fuel.

Good old recycling

Almost every college has recycling bins and trash cans on its territory. The faculty and staff should be responsible for what and where they throw away – it will be a good example for every student.

Creating eco-friendly rules in a campus

  • Turn off everything
  • Using LED light bulbs
  • Reduce, reuse, recycle
  • Water-usage control (only a 5-minute shower)
  • Buy recyclable and eco products, e.g. you can even find eco friendly wooden watches these days.
  • Use power bars
  • Wash cups and plates, don’t use disposable paper or plastic utensils
  • Walk, bike and use public transport instead of a car

If you at a moment of decision which higher educational institution to choose – go ahead to pick a “go green” university which has at least some of point mentioned above!

Don’t close your eyes to truth – the climate change, the nuclear waste, etc.

With all these actions, even the little ones, we may protect the environment together and live a sustainable life!

If this article written by a birdie essay writer was helpful and met your expectations – you can find other related works and even obtain help with your essay if needed!

Wish you a good green luck!